#include <bits/stdc++.h>

#define speed cin.tie(0); ios::sync_with_stdio(0)
#define cinv(v) for (auto& e : v) cin >> e;
#define all(v) v.begin(), v.end()
#define has(s, e) s.count(e)

using namespace std;
using ll = long long;
using point = array<int, 2>;

int digc(int n) {
    int result = 0;
    while (0 < n) {
        n /= 10;
        result++;
    }
    return result;
}

int main() {
    speed;

    int cnt = 3;
    while (cnt--) {
        int A, B, N;
        cin >> A >> B >> N;
        int mn = lcm(A, B), dc = digc(mn);
        if (N < dc) {
            cout << -1;
        } else {
            cout << mn;
            int rem = N - dc;
            while (rem--) {
                cout << 0;
            }
        }
        cout << '\n';
    }
}